Circuit breaker



July 7, y 1942. J. A. vox( y CIRCUIT BREAKER Filed Feb. 21, 19391NVENT0R Jgsqp d. (Yay.

ATTogNEYC Patented July 7, 1942 CIRCUIT BREAKER Joseph A. Coy,Cincinnati, Ohio, assigner to The Wadsworth Electric Mfg. Co., Inc.,Covington, Ky., a corporation of Kentucky Application February 2l, 1939,Serial No. 257,641

y 2 Claims. A(Cl. 7260-89) This invention relates to im-provements incircuit breakers and is particularly directed to circuit interruptersfor use in light capacity circuits such as in residential wiring or thelike.

It is an object of this invention to provide an improved circuit breakerhaving certain structural elements which cooperate to provide a meansfor conducting one leg of the protected electrical circuit through saidbreaker.

Another object of the invention is to provide a breaker of simplifiedconstruction which results in a compact and relatively small devicewhich may `be made at a comparatively small cost.

Other objects will be apparent from the iollowing specification anddrawing, in which:

Fig. 1 is a longitudinal cross-sectional view through my circuitbreaker.

Fig. 2 is a wiring diagram for the circuit employing my interrupter.

The embodiment of my invention comprises a circuit breaker 4 having amagnetic coil 5, a thermal responsive switch 6 and a circuit switch 'Imounted as a unit upon a non-conductive base 8. The means responsive topredetermined overload conditions in the protected circuit comprises themagnetic coil, commonly termed a solenoid, which has two verticallyAspaced metallic plates 9 and I0 mounted on the base 8 by means ofintegral horizontal portions I I and I2 respectively. The portion I2serves as a contact fastening plate for the load wire I3, the portion IIbeing held in electrical contact with a lower horizontal portion ofswitch mechanism 1 by means of screw II 0. The plates are provided withcentral apertures for receiving a hollow cylindrical -core I4, a sleeveI made of insulating material encircling said core and insulating itfrom the plates. The ends of the core project from the plates and areprovided with exterior threads for receiving caps |50 and IS to completethe housing for an armature I'I, a plunger I8 and a compression springI9. Magnetic coil 5 is wound over the sleeve I5 and between the plates 9and I0 and is insulated from said plates, the ends thereof beingsoldered to each of said plates as indicated at 2I and 22.

A thermal responsive switch B for conditioning the solenoid may be usedin my breaker and may take the form of flange 220 of the plate I0 bymeans of screw 230. The free end of the element normally contacts ange23 of the plate 9. The element is electrically conductive and flexesupwardly when subject to heat generated by electrical resistance set uptherein in the Well-known manner.

The outer end of the portion II is electrically connected to the lowerconnecting portion 24 of two spa-ced vertical members of the switch, oneof which is indicated as 25. These members carry between them, by meansof connecting pins, the operative mechanism of the switch whichcomprises a breaker arm 26 pivoted between the vertical members by meansof pin 2l. In normally closed position, the outer end of the breaker`arm engages spring contact 28, said contact being electricallyconnected to plate 29 which carries a contact screw 30 for binding theend of line wire 3I. The breaker arm is normally held in engagement withspring contact by means of a jointed link 32, pivoted to said armintermediate its ends by pin 33. The upper end of the link is freelypinned to lever 34, the latter being rotatably mounted to the spacedvertical members by means of pin 35. The free end of the lever isprovided with an elongated slot 36 which receives a pin 31 rigidlymounted on L-shaped lever 38, the latter lever 1 being mounted to thevertical members by means of pin 40. A handle 4I is fastened to theupper portion of the lever by screw 42. A tension spring 43 is fastenedto the outer end of the breaker arm and to an extension 44 of the lever38, biasing said arm and lever to open position.

It will be noted that in normal closed breaker arm position, the jointedportion 45 of the link 32 is beyond dead center, the lever being heldrigid by the lower portion thereof engaging an -abutment 46 formed onthe upper portion of the link whilst the pin 3l takes a position in thelowermost portion of the slot 36 which indicates a point beyond deadcenter with reference t0 the linkage elements 34 and 38 and the force`exerted on the parts by tension spring 43. The switch is adapted toopen the circuit when the breaker arm disengages from the spring contact28. This is accomplished when the cir- -cuit has been subjected to anoverload sufficient to build up a magnet field in the coil and draw thearmature into alignment with it thus moving plunger I8 to contact thelink 32 at jointed portion 45. This action results in the collapse ofthe link, permitting the breaker arm and lever 38 to be drawn towardeach other to break the circuit. The switch is reset by rotating handle4I in a clockwise movement which adjusts the jointed links 32 andreturns the switch parts to a position indicated in Fig. 1.

As shown in the diagram (Fig. 2), like reference numerals refer tosimilar elements--and as indicated in the foregoing description, oneside of the magnetic coil is connected to a suitable translating device41 by means of Wire I3, line 48 being led from said device to theservice circuit. The other side of the coil is connected to the breakerarm 26, which in turn engages spring contact 28 communicating with theservice line 3| to` complete the circuit. It will therefore be notedthat the electrical circuit through the breaker is plate foot portionI2, plate I0, solenoid coil 5, plate 9, plate foot portion H; lowerconnecting portion 24 of the U-shaped switch supporting frame 25,breaker arm 26, stationary contact 28 and plate 29. The structuralelements of the breaker therefore function as a means of conducting oneleg of the protected circuit through said solenoid and thus provides asimplified and economically constructed circuit breaker.

What is claimed is:

1. An interrupter for an electric circuit comprising an electrically,non-conductive base; a breaker arm movable to open or close the circuit;switch mechanism connected to the arm for maintaining said arm in openor closed circuit positions; a U-shaped frame supporting the breaker armand the switch mechanism between the vertical side members thereof, andhaving its lower, horizontal portion resting upon the base, said framebeing in electrical engagement with the breaker arm and serving as acurrent conductor for the circuit; means responsive to overloadconditions in the circuit positioned adjacent the switch mechanism andassociated therewith to open the circuit and comprising a solenoidhaving two L-shaped, electrically conductive plates with their footportions formed in divergent, horizontal relationship and resting uponthe base; the plates having aligned apertures formed therein; a coreextending through the apertures and supported by the plates; means forinsulating the core from the plates; a coil Wound on the core and havingeach terminus in electrical engagement with one of the plates; the endof one of the said foot portions being in contact with the lowerhorizontal portion of the U-shaped frame; means for locking saidportions together and binding them to the base; and an electricalcontact on the end of the other foot portion.

2. An interrupter for an electric circuit comprising an electrically,non-conductive base; a breaker arm movable to open or close the Circuit;switch mechanism connected to the arm for maintaining said arm in openor closed circuit positions; a U-shaped frame supporting the breaker armand the switch mechanism between the vertical side members thereof, andhaving its lower, horizontal portion resting upon the base, said framebeing in electrical engagement with the breaker arm and serving as acurrent conductor for the circuit; means responsive to overloadconditions in the circuit positioned adjacent the switch mechanism andassociated therewith to open the circuit and comprising a solenoidhaving two L-shaped, electrically conductive plates with their footportions formed in divergent, horizontal relationship and resting uponthe base; the plates having aligned apertures formed therein; a coreextending through the apertures and supported by the plates; an armaturemovable Within the core; a plunger rod extending from the core, saidcore being mounted between the plates in a position to permit actuationof the switch mechanisln by the rod; means for insulating the core fromthe plates; a coil wound on the core and having each terminus inelectrical engagement with one of the plates; the end of one of the saidfoot portions being in contact with the lower horizontal portion of theU-shaped frame; means for locking said portions together and bindingthem to the base; and an electrical contact on the end .of the otherfoot portion.

JOSEPH A. COY.

